The first-ever sabotage of a passenger plane

It is known that Flight 11 was the first-ever sabotage of a commercial jet airliner in the United States of America. Interestingly enough I have come across the details of what is believed to be the first-ever sabotage of a passenger aircraft anywhere in the world. For those who are interested here is the small link to the wikipedia article. Makes for an interesting read. And oddly enough, despite its significance, it too has never had a memorial. 

http://en.wikipedia.org/wiki/United_Airlines_crash_near_Chesterton

Also, just to stop press, a link to the 1933 newspaper article from the Citizen Advertiser newspaper in New York:

http://fultonhistory.com/newspaper%202/Auburn%20NY%20Citizen%20Advertiser/Auburn%20NY%20Citizen%20Advertiser%201933.pdf/Newspaper%20Auburn%20NY%20Citizen%20Advertiser%201933%20-%200105.PDF